Fix PYTHIA decay problem.
If particle decays of final states with PYTHIA is enabled and more than 10 particles appear (which can happen due to photons) the provided array (10 elements) is to small. Increase the array size to 20.
If particle decays of final states with PYTHIA is enabled and more than 10 particles appear (which can happen due to photons) the provided array (10 elements) is to small. Increase the array size to 20.